Preheat your oven to 220cPut the tamari, water and cayenne into a bowl, add the cauliflower and mix until all of the cauliflower is covered. Put the cauliflower onto a baking tray.Add the mushrooms to the bowl and mix into the liquid. Put them onto the baking tray. The sweet potato doesn't need any oil so just put those onto the tray as they are, making sure they do not overlap. Bake until just cooked, this should take around 10-15 minutes. For the hummus blend all of the ingredients with a hand blender or in a food processor until smooth. Add a little more water if the blend needs more liquid to turn and blend the mixture well. Pour into a bowl and serve with the tamari baked veg dippers.